Ester solvents and compositions



Patented Sept. 12,

, r 1,926,511 p ESTER: SQLVENTSAND COMPOSITIONS 7 Guy H. Buchanan, Westfield, N.- 1, assignor to American Cyanamid Company, New York, 'N. 1., a corporation of Maine 7 No Drawing. 7 Application'Fe bruary 25, 1930 a Serial No'.431,346. a p

6 Claims. (01. 13449) This invention relates to solvents, and more the like, such as cellulose nitrate. g

In'the preparation of lacquer compositions and the like containing cellulose esters such as cellulose acetate and cellulose nitrate, many solvents I have been suggested andused. These solvents vary in boiling point and the drying time of the finished composition is usually regulated by suit- 0 able combinations of these solvents.

This application is a continuation in part .of my co-pending application, Serial Number 162,-

- particularly tosolvents for esters of cellulose and 306, describing my solvents and their uses.

pounds are eminently suitable for use as solvents,

' particularly. in cellulose ester compositions.

These solvents may. be easily and economically prepared and have boiling points whichfadapt ester lacquer art and the like.

I have discovered that the alkylesters of oc-hYdIOXY-iSO butyric acid, in which the alkyl radical contains more-than two carbon-atoms, and preferably 3 to '5, are especially suitable as cellulose ester solvents. This groupof substances hydrochloric acid. Thus, to prepare the butyl- 40 ester, the cyanhydrin is. reacted with butyl alco hol in. the presence of the acid, using the amount of water required by the chemical equation. The" mixture is heated till the cyanhydrin is com pletely reacted. The, precipitated ammonium 4 additional alcohol, the filtrate and washings be-' ing combined, and from .thiscombination the ester is separatedfrom the excess alcohol by fractional distillation. The butyl a-hydroxy,

butyrate has a boiling point of about 182C.

The acetone cyanhydrin may be prepared by the addition of liquid hydrocyanic acidto substantiallyv anhydrous acetone, using a small amount of alcoholiccaustic soda solution asthe catalyst. The other a-hydroxy butyric esters I have discovered that a certain class of come them to wide use in, such arts as the cellulosechloride is filtered'off and maybe washed with may be prepared in a manner similar to that described, the butyrates increasing in boiling point I with theincrease of carbon atoms in the alkyl radical, the amyl butyrate" boiling at about 193 C., and the propyl below 180. C. t g All of these esters .of a-hYdIOXY butyric acid are excellent solvents, the change in thealkyl radical having comparatively little efiect upon the solvent properties,,the only important difierenc'e being in the boiling point and rate of -evaporation ofthe-esters'. It is obviousfthat methods other than described may be used in preparing my esters without departing from thespiritof the in vention. Thesolvents which I have discovered aresuitable for-usewith the various esters and ethersof cellulose including nitrocellulose, cellulose acetate, natural and synthetic resins, gums,f

etc. It isto be understood thattheinvention is susceptible of manyvariations without departing from the scope thereof except as defined in the 5. 1

claims appended hereto. V,

I claim:' v

1. A composition of matter comprising a cellu- 4 lose esterand an aliphatic ester of a-hydroxy iso butyric acid inwhich the alkyl radicalcontains 3 ,more than two carbon atoms. The esterbeing .compatiblewith the cellulose ester.. I

2. A composition of matter comprlsinga celllulose nitrate and an aliphatic ester of a-hydroxy.

' iso butyric. acidin whichthe alkyl'radical contains more'than two carbon atoms, the; ester being compatible with the cellulose ester.

"'13. A composition of matter comprising'a cellulose ester and an aliphatic esterof a-hydroxy iso butyric acid in which the alkyl radical contains from three to five carbon atoms. 7 I

4. A composition of matter comprising a cellulose nitrate and an aliphatic ester of a-hYdlOXY iso butyric acid in which the alkyl radical contains from three to five carbon atoms.

5. Acomposition of 'matter comprising a' cellulose ester. and a'butyl ester of a-hydroxy iso butyric acid. i l

6. A composition of, matter comprising a cellulose nitrate and a butyl ester of u-hydroxy iso 1 butyric acid., i

GUY H. BUCHANAN.

PA ENTl I CE 1 Q 

